package net.sf.jailer.util;

import java.io.Closeable;
import java.io.IOException;

/**
 * <p>Encodes and decodes to and from Base64 notation.</p>
 * <p>Homepage: <a href="http://iharder.net/base64">http://iharder.net/base64</a>.</p>
 *
 * <p>The <tt>options</tt> parameter, which appears in a few places, is used to pass 
 * several pieces of information to the encoder. In the "higher level" methods such as 
 * encodeBytes( bytes, options ) the options parameter can be used to indicate such 
 * things as first gzipping the bytes before encoding them, not inserting linefeeds 
 * (though that breaks strict Base64 compatibility), and encoding using the URL-safe 
 * and Ordered dialects.</p>
 *
 * <p>The constants defined in Base64 can be OR-ed together to combine options, so you 
 * might make a call like this:</p>
 *
 * <code>String encoded = Base64.encodeBytes( mybytes, Base64.GZIP | Base64.DONT_BREAK_LINES );</code>
 *
 * <p>to compress the data before encoding it and then making the output have no newline characters.</p>
 *
 *
 * <p>
 * Change Log:
 * </p>
 * <ul>
 *  <li>v2.2.2 - Fixed encodeFileToFile and decodeFileToFile to use the
 *   Base64.InputStream class to encode and decode on the fly which uses
 *   less memory than encoding/decoding an entire file into memory before writing.</li>
 *  <li>v2.2.1 - Fixed bug using URL_SAFE and ORDERED encodings. Fixed bug
 *   when using very small files (~< 40 bytes).</li>
 *  <li>v2.2 - Added some helper methods for encoding/decoding directly from
 *   one file to the next. Also added a main() method to support command line
 *   encoding/decoding from one file to the next. Also added these Base64 dialects:
 *   <ol>
 *   <li>The default is RFC3548 format.</li>
 *   <li>Calling Base64.setFormat(Base64.BASE64_FORMAT.URLSAFE_FORMAT) generates
 *   URL and file name friendly format as described in Section 4 of RFC3548.
 *   http://www.faqs.org/rfcs/rfc3548.html</li>
 *   <li>Calling Base64.setFormat(Base64.BASE64_FORMAT.ORDERED_FORMAT) generates
 *   URL and file name friendly format that preserves lexical ordering as described
 *   in http://www.faqs.org/qa/rfcc-1940.html</li>
 *   </ol>
 *   Special thanks to Jim Kellerman at <a href="http://www.powerset.com/">http://www.powerset.com/</a>
 *   for contributing the new Base64 dialects.
 *  </li>
 * 
 *  <li>v2.1 - Cleaned up javadoc comments and unused variables and methods. Added
 *   some convenience methods for reading and writing to and from files.</li>
 *  <li>v2.0.2 - Now specifies UTF-8 encoding in places where the code fails on systems
 *   with other encodings (like EBCDIC).</li>
 *  <li>v2.0.1 - Fixed an error when decoding a single byte, that is, when the
 *   encoded data was a single byte.</li>
 *  <li>v2.0 - I got rid of methods that used booleans to set options. 
 *   Now everything is more consolidated and cleaner. The code now detects
 *   when data that's being decoded is gzip-compressed and will decompress it
 *   automatically. Generally things are cleaner. You'll probably have to
 *   change some method calls that you were making to support the new
 *   options format (<tt>int</tt>s that you "OR" together).</li>
 *  <li>v1.5.1 - Fixed bug when decompressing and decoding to a             
 *   byte[] using <tt>decode( String s, boolean gzipCompressed )</tt>.      
 *   Added the ability to "suspend" encoding in the Output Stream so        
 *   you can turn on and off the encoding if you need to embed base64       
 *   data in an otherwise "normal" stream (like an XML file).</li>  
 *  <li>v1.5 - Output stream pases on flush() command but doesn't do anything itself.
 *      This helps when using GZIP streams.
 *      Added the ability to GZip-compress objects before encoding them.</li>
 *  <li>v1.4 - Added helper methods to read/write files.</li>
 *  <li>v1.3.6 - Fixed OutputStream.flush() so that 'position' is reset.</li>
 *  <li>v1.3.5 - Added flag to turn on and off line breaks. Fixed bug in input stream
 *      where last buffer being read, if not completely full, was not returned.</li>
 *  <li>v1.3.4 - Fixed when "improperly padded stream" error was thrown at the wrong time.</li>
 *  <li>v1.3.3 - Fixed I/O streams which were totally messed up.</li>
 * </ul>
 *
 * <p>
 * I am placing this code in the Public Domain. Do with it as you will.
 * This software comes with no guarantees or warranties but with
 * plenty of well-wishing instead!
 * Please visit <a href="http://iharder.net/base64">http://iharder.net/base64</a>
 * periodically to check for updates or to contribute improvements.
 * </p>
 *
 * @author Robert Harder
 * @author rob@iharder.net
 * @version 2.2.2
 */
public class Base64
{
	
/* ********  P U B L I C   F I E L D S  ******** */   
	
	
	/** No options specified. Value is zero. */
	public final static int NO_OPTIONS = 0;
	
	/** Specify encoding. */
	public final static int ENCODE = 1;
	
	
	/** Specify decoding. */
	public final static int DECODE = 0;
	
	
	/** Specify that data should be gzip-compressed. */
	public final static int GZIP = 2;
	
	
	/** Don't break lines when encoding (violates strict Base64 specification) */
	public final static int DONT_BREAK_LINES = 8;
	
	/** 
	 * Encode using Base64-like encoding that is URL- and Filename-safe as described
	 * in Section 4 of RFC3548: 
	 * <a href="http://www.faqs.org/rfcs/rfc3548.html">http://www.faqs.org/rfcs/rfc3548.html</a>.
	 * It is important to note that data encoded this way is <em>not</em> officially valid Base64, 
	 * or at the very least should not be called Base64 without also specifying that is
	 * was encoded using the URL- and Filename-safe dialect.
	 */
	 public final static int URL_SAFE = 16;
	 
	 
	 /**
	  * Encode using the special "ordered" dialect of Base64 described here:
	  * <a href="http://www.faqs.org/qa/rfcc-1940.html">http://www.faqs.org/qa/rfcc-1940.html</a>.
	  */
	 public final static int ORDERED = 32;
	
	
/* ********  P R I V A T E   F I E L D S  ******** */  
	
	
	/** Maximum line length (76) of Base64 output. */
	private final static int MAX_LINE_LENGTH = 76;
	
	
	/** The equals sign (=) as a byte. */
	private final static byte EQUALS_SIGN = (byte)'=';
	
	
	/** The new line character (\n) as a byte. */
	private final static byte NEW_LINE = (byte)'\n';
	
	
	/** Preferred encoding. */
	private final static String PREFERRED_ENCODING = "UTF-8";
	
	
	// I think I end up not using the BAD_ENCODING indicator.
	//private final static byte BAD_ENCODING    = -9; // Indicates error in encoding
	private final static byte WHITE_SPACE_ENC = -5; // Indicates white space in encoding
	private final static byte EQUALS_SIGN_ENC = -1; // Indicates equals sign in encoding
	
	
/* ********  S T A N D A R D   B A S E 6 4   A L P H A B E T  ******** */	
	
	/** The 64 valid Base64 values. */
	//private final static byte[] ALPHABET;
	/* Host platform me be something funny like EBCDIC, so we hardcode these values. */
	private final static byte[] _STANDARD_ALPHABET =
	{
		(byte)'A', (byte)'B', (byte)'C', (byte)'D', (byte)'E', (byte)'F', (byte)'G',
		(byte)'H', (byte)'I', (byte)'J', (byte)'K', (byte)'L', (byte)'M', (byte)'N',
		(byte)'O', (byte)'P', (byte)'Q', (byte)'R', (byte)'S', (byte)'T', (byte)'U', 
		(byte)'V', (byte)'W', (byte)'X', (byte)'Y', (byte)'Z',
		(byte)'a', (byte)'b', (byte)'c', (byte)'d', (byte)'e', (byte)'f', (byte)'g',
		(byte)'h', (byte)'i', (byte)'j', (byte)'k', (byte)'l', (byte)'m', (byte)'n',
		(byte)'o', (byte)'p', (byte)'q', (byte)'r', (byte)'s', (byte)'t', (byte)'u', 
		(byte)'v', (byte)'w', (byte)'x', (byte)'y', (byte)'z',
		(byte)'0', (byte)'1', (byte)'2', (byte)'3', (byte)'4', (byte)'5', 
		(byte)'6', (byte)'7', (byte)'8', (byte)'9', (byte)'+', (byte)'/'
	};
	
	
	/** 
	 * Translates a Base64 value to either its 6-bit reconstruction value
	 * or a negative number indicating some other meaning.
	 **/
	private final static byte[] _STANDARD_DECODABET =
	{   
		-9,-9,-9,-9,-9,-9,-9,-9,-9,                 // Decimal  0 -  8
		-5,-5,                                      // Whitespace: Tab and Linefeed
		-9,-9,                                      // Decimal 11 - 12
		-5,                                         // Whitespace: Carriage Return
		-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 14 - 26
		-9,-9,-9,-9,-9,                             // Decimal 27 - 31
		-5,                                         // Whitespace: Space
		-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,              // Decimal 33 - 42
		62,                                         // Plus sign at decimal 43
		-9,-9,-9,                                   // Decimal 44 - 46
		63,                                         // Slash at decimal 47
		52,53,54,55,56,57,58,59,60,61,              // Numbers zero through nine
		-9,-9,-9,                                   // Decimal 58 - 60
		-1,                                         // Equals sign at decimal 61
		-9,-9,-9,                                      // Decimal 62 - 64
		0,1,2,3,4,5,6,7,8,9,10,11,12,13,            // Letters 'A' through 'N'
		14,15,16,17,18,19,20,21,22,23,24,25,        // Letters 'O' through 'Z'
		-9,-9,-9,-9,-9,-9,                          // Decimal 91 - 96
		26,27,28,29,30,31,32,33,34,35,36,37,38,     // Letters 'a' through 'm'
		39,40,41,42,43,44,45,46,47,48,49,50,51,     // Letters 'n' through 'z'
		-9,-9,-9,-9                                 // Decimal 123 - 126
		/*,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 127 - 139
		-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 140 - 152
		-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 153 - 165
		-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 166 - 178
		-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 179 - 191
		-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 192 - 204
		-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 205 - 217
		-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 218 - 230
		-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 231 - 243
		-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9         // Decimal 244 - 255 */
	};
	
	
/* ********  U R L   S A F E   B A S E 6 4   A L P H A B E T  ******** */
	
	/**
	 * Used in the URL- and Filename-safe dialect described in Section 4 of RFC3548: 
	 * <a href="http://www.faqs.org/rfcs/rfc3548.html">http://www.faqs.org/rfcs/rfc3548.html</a>.
	 * Notice that the last two bytes become "hyphen" and "underscore" instead of "plus" and "slash."
	 */
	private final static byte[] _URL_SAFE_ALPHABET =
	{
	  (byte)'A', (byte)'B', (byte)'C', (byte)'D', (byte)'E', (byte)'F', (byte)'G',
	  (byte)'H', (byte)'I', (byte)'J', (byte)'K', (byte)'L', (byte)'M', (byte)'N',
	  (byte)'O', (byte)'P', (byte)'Q', (byte)'R', (byte)'S', (byte)'T', (byte)'U', 
	  (byte)'V', (byte)'W', (byte)'X', (byte)'Y', (byte)'Z',
	  (byte)'a', (byte)'b', (byte)'c', (byte)'d', (byte)'e', (byte)'f', (byte)'g',
	  (byte)'h', (byte)'i', (byte)'j', (byte)'k', (byte)'l', (byte)'m', (byte)'n',
	  (byte)'o', (byte)'p', (byte)'q', (byte)'r', (byte)'s', (byte)'t', (byte)'u', 
	  (byte)'v', (byte)'w', (byte)'x', (byte)'y', (byte)'z',
	  (byte)'0', (byte)'1', (byte)'2', (byte)'3', (byte)'4', (byte)'5', 
	  (byte)'6', (byte)'7', (byte)'8', (byte)'9', (byte)'-', (byte)'_'
	};
	
	/**
	 * Used in decoding URL- and Filename-safe dialects of Base64.
	 */
	private final static byte[] _URL_SAFE_DECODABET =
	{   
	  -9,-9,-9,-9,-9,-9,-9,-9,-9,                 // Decimal  0 -  8
	  -5,-5,                                      // Whitespace: Tab and Linefeed
	  -9,-9,                                      // Decimal 11 - 12
	  -5,                                         // Whitespace: Carriage Return
	  -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 14 - 26
	  -9,-9,-9,-9,-9,                             // Decimal 27 - 31
	  -5,                                         // Whitespace: Space
	  -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,              // Decimal 33 - 42
	  -9,                                         // Plus sign at decimal 43
	  -9,                                         // Decimal 44
	  62,                                         // Minus sign at decimal 45
	  -9,                                         // Decimal 46
	  -9,                                         // Slash at decimal 47
	  52,53,54,55,56,57,58,59,60,61,              // Numbers zero through nine
	  -9,-9,-9,                                   // Decimal 58 - 60
	  -1,                                         // Equals sign at decimal 61
	  -9,-9,-9,                                   // Decimal 62 - 64
	  0,1,2,3,4,5,6,7,8,9,10,11,12,13,            // Letters 'A' through 'N'
	  14,15,16,17,18,19,20,21,22,23,24,25,        // Letters 'O' through 'Z'
	  -9,-9,-9,-9,                                // Decimal 91 - 94
	  63,                                         // Underscore at decimal 95
	  -9,                                         // Decimal 96
	  26,27,28,29,30,31,32,33,34,35,36,37,38,     // Letters 'a' through 'm'
	  39,40,41,42,43,44,45,46,47,48,49,50,51,     // Letters 'n' through 'z'
	  -9,-9,-9,-9                                 // Decimal 123 - 126
	  /*,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 127 - 139
	  -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 140 - 152
	  -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 153 - 165
	  -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 166 - 178
	  -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 179 - 191
	  -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 192 - 204
	  -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 205 - 217
	  -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 218 - 230
	  -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 231 - 243
	  -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9         // Decimal 244 - 255 */
	};



/* ********  O R D E R E D   B A S E 6 4   A L P H A B E T  ******** */

	/**
	 * I don't get the point of this technique, but it is described here:
	 * <a href="http://www.faqs.org/qa/rfcc-1940.html">http://www.faqs.org/qa/rfcc-1940.html</a>.
	 */
	private final static byte[] _ORDERED_ALPHABET =
	{
	  (byte)'-',
	  (byte)'0', (byte)'1', (byte)'2', (byte)'3', (byte)'4',
	  (byte)'5', (byte)'6', (byte)'7', (byte)'8', (byte)'9',
	  (byte)'A', (byte)'B', (byte)'C', (byte)'D', (byte)'E', (byte)'F', (byte)'G',
	  (byte)'H', (byte)'I', (byte)'J', (byte)'K', (byte)'L', (byte)'M', (byte)'N',
	  (byte)'O', (byte)'P', (byte)'Q', (byte)'R', (byte)'S', (byte)'T', (byte)'U',
	  (byte)'V', (byte)'W', (byte)'X', (byte)'Y', (byte)'Z',
	  (byte)'_',
	  (byte)'a', (byte)'b', (byte)'c', (byte)'d', (byte)'e', (byte)'f', (byte)'g',
	  (byte)'h', (byte)'i', (byte)'j', (byte)'k', (byte)'l', (byte)'m', (byte)'n',
	  (byte)'o', (byte)'p', (byte)'q', (byte)'r', (byte)'s', (byte)'t', (byte)'u',
	  (byte)'v', (byte)'w', (byte)'x', (byte)'y', (byte)'z'
	};
	
	/**
	 * Used in decoding the "ordered" dialect of Base64.
	 */
	private final static byte[] _ORDERED_DECODABET =
	{   
	  -9,-9,-9,-9,-9,-9,-9,-9,-9,                 // Decimal  0 -  8
	  -5,-5,                                      // Whitespace: Tab and Linefeed
	  -9,-9,                                      // Decimal 11 - 12
	  -5,                                         // Whitespace: Carriage Return
	  -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 14 - 26
	  -9,-9,-9,-9,-9,                             // Decimal 27 - 31
	  -5,                                         // Whitespace: Space
	  -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,              // Decimal 33 - 42
	  -9,                                         // Plus sign at decimal 43
	  -9,                                         // Decimal 44
	  0,                                          // Minus sign at decimal 45
	  -9,                                         // Decimal 46
	  -9,                                         // Slash at decimal 47
	  1,2,3,4,5,6,7,8,9,10,                       // Numbers zero through nine
	  -9,-9,-9,                                   // Decimal 58 - 60
	  -1,                                         // Equals sign at decimal 61
	  -9,-9,-9,                                   // Decimal 62 - 64
	  11,12,13,14,15,16,17,18,19,20,21,22,23,     // Letters 'A' through 'M'
	  24,25,26,27,28,29,30,31,32,33,34,35,36,     // Letters 'N' through 'Z'
	  -9,-9,-9,-9,                                // Decimal 91 - 94
	  37,                                         // Underscore at decimal 95
	  -9,                                         // Decimal 96
	  38,39,40,41,42,43,44,45,46,47,48,49,50,     // Letters 'a' through 'm'
	  51,52,53,54,55,56,57,58,59,60,61,62,63,     // Letters 'n' through 'z'
	  -9,-9,-9,-9                                 // Decimal 123 - 126
	  /*,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 127 - 139
		-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 140 - 152
		-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 153 - 165
		-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 166 - 178
		-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 179 - 191
		-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 192 - 204
		-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 205 - 217
		-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 218 - 230
		-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,     // Decimal 231 - 243
		-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9         // Decimal 244 - 255 */
	};

	
/* ********  D E T E R M I N E   W H I C H   A L H A B E T  ******** */


	/**
	 * Returns one of the _SOMETHING_ALPHABET byte arrays depending on
	 * the options specified.
	 * It's possible, though silly, to specify ORDERED and URLSAFE
	 * in which case one of them will be picked, though there is
	 * no guarantee as to which one will be picked.
	 */
	private final static byte[] getAlphabet( int options )
	{
		if( (options & URL_SAFE) == URL_SAFE ) return _URL_SAFE_ALPHABET;
		else if( (options & ORDERED) == ORDERED ) return _ORDERED_ALPHABET;
		else return _STANDARD_ALPHABET;
		
	}	// end getAlphabet
	
	
	/**
	 * Returns one of the _SOMETHING_DECODABET byte arrays depending on
	 * the options specified.
	 * It's possible, though silly, to specify ORDERED and URL_SAFE
	 * in which case one of them will be picked, though there is
	 * no guarantee as to which one will be picked.
	 */
	private final static byte[] getDecodabet( int options )
	{
		if( (options & URL_SAFE) == URL_SAFE ) return _URL_SAFE_DECODABET;
		else if( (options & ORDERED) == ORDERED ) return _ORDERED_DECODABET;
		else return _STANDARD_DECODABET;
		
	}	// end getAlphabet
		

	
	/** Defeats instantiation. */
	private Base64(){}
	

	/**
	 * Encodes or decodes two files from the command line;
	 * <strong>feel free to delete this method (in fact you probably should)
	 * if you're embedding this code into a larger program.</strong>
	 */
	public final static void main( String[] args )
	{
		if( args.length < 3 ){
			usage("Not enough arguments.");
		}   // end if: args.length < 3
		else {
			String flag = args[0];
			String infile = args[1];
			String outfile = args[2];
			if( flag.equals( "-e" ) ){
				Base64.encodeFileToFile( infile, outfile );
			}   // end if: encode
			else if( flag.equals( "-d" ) ) {
				Base64.decodeFileToFile( infile, outfile );
			}   // end else if: decode    
			else {
				usage( "Unknown flag: " + flag );
			}   // end else    
		}   // end else
	}   // end main

	/**
	 * Prints command line usage.
	 *
	 * @param msg A message to include with usage info.
	 */
	private final static void usage( String msg )
	{
		System.err.println( msg );
		System.err.println( "Usage: java Base64 -e|-d inputfile outputfile" );
	}   // end usage
	
	
/* ********  E N C O D I N G   M E T H O D S  ******** */    
	
	
	/**
	 * Encodes up to the first three bytes of array <var>threeBytes</var>
	 * and returns a four-byte array in Base64 notation.
	 * The actual number of significant bytes in your array is
	 * given by <var>numSigBytes</var>.
	 * The array <var>threeBytes</var> needs only be as big as
	 * <var>numSigBytes</var>.
	 * Code can reuse a byte array by passing a four-byte array as <var>b4</var>.
	 *
	 * @param b4 A reusable byte array to reduce array instantiation
	 * @param threeBytes the array to convert
	 * @param numSigBytes the number of significant bytes in your array
	 * @return four byte array in Base64 notation.
	 * @since 1.5.1
	 */
	private static byte[] encode3to4( byte[] b4, byte[] threeBytes, int numSigBytes, int options )
	{
		encode3to4( threeBytes, 0, numSigBytes, b4, 0, options );
		return b4;
	}   // end encode3to4

	
	/**
	 * <p>Encodes up to three bytes of the array <var>source</var>
	 * and writes the resulting four Base64 bytes to <var>destination</var>.
	 * The source and destination arrays can be manipulated
	 * anywhere along their length by specifying 
	 * <var>srcOffset</var> and <var>destOffset</var>.
	 * This method does not check to make sure your arrays
	 * are large enough to accomodate <var>srcOffset</var> + 3 for
	 * the <var>source</var> array or <var>destOffset</var> + 4 for
	 * the <var>destination</var> array.
	 * The actual number of significant bytes in your array is
	 * given by <var>numSigBytes</var>.</p>
	 * <p>This is the lowest level of the encoding methods with
	 * all possible parameters.</p>
	 *
	 * @param source the array to convert
	 * @param srcOffset the index where conversion begins
	 * @param numSigBytes the number of significant bytes in your array
	 * @param destination the array to hold the conversion
	 * @param destOffset the index where output will be put
	 * @return the <var>destination</var> array
	 * @since 1.3
	 */
	private static byte[] encode3to4( 
	 byte[] source, int srcOffset, int numSigBytes,
	 byte[] destination, int destOffset, int options )
	{
		byte[] ALPHABET = getAlphabet( options ); 
	
		//           1         2         3  
		// 01234567890123456789012345678901 Bit position
		// --------000000001111111122222222 Array position from threeBytes
		// --------|    ||    ||    ||    | Six bit groups to index ALPHABET
		//          >>18  >>12  >> 6  >> 0  Right shift necessary
		//                0x3f  0x3f  0x3f  Additional AND
		
		// Create buffer with zero-padding if there are only one or two
		// significant bytes passed in the array.
		// We have to shift left 24 in order to flush out the 1's that appear
		// when Java treats a value as negative that is cast from a byte to an int.
		int inBuff =   ( numSigBytes > 0 ? ((source[ srcOffset     ] << 24) >>>  8) : 0 )
					 | ( numSigBytes > 1 ? ((source[ srcOffset + 1 ] << 24) >>> 16) : 0 )
					 | ( numSigBytes > 2 ? ((source[ srcOffset + 2 ] << 24) >>> 24) : 0 );

		switch( numSigBytes )
		{
			case 3:
				destination[ destOffset     ] = ALPHABET[ (inBuff >>> 18)        ];
				destination[ destOffset + 1 ] = ALPHABET[ (inBuff >>> 12) & 0x3f ];
				destination[ destOffset + 2 ] = ALPHABET[ (inBuff >>>  6) & 0x3f ];
				destination[ destOffset + 3 ] = ALPHABET[ (inBuff       ) & 0x3f ];
				return destination;
				
			case 2:
				destination[ destOffset     ] = ALPHABET[ (inBuff >>> 18)        ];
				destination[ destOffset + 1 ] = ALPHABET[ (inBuff >>> 12) & 0x3f ];
				destination[ destOffset + 2 ] = ALPHABET[ (inBuff >>>  6) & 0x3f ];
				destination[ destOffset + 3 ] = EQUALS_SIGN;
				return destination;
				
			case 1:
				destination[ destOffset     ] = ALPHABET[ (inBuff >>> 18)        ];
				destination[ destOffset + 1 ] = ALPHABET[ (inBuff >>> 12) & 0x3f ];
				destination[ destOffset + 2 ] = EQUALS_SIGN;
				destination[ destOffset + 3 ] = EQUALS_SIGN;
				return destination;
				
			default:
				return destination;
		}   // end switch
	}   // end encode3to4
	
	
	
	/**
	 * Serializes an object and returns the Base64-encoded
	 * version of that serialized object. If the object
	 * cannot be serialized or there is another error,
	 * the method will return <tt>null</tt>.
	 * The object is not GZip-compressed before being encoded.
	 *
	 * @param serializableObject The object to encode
	 * @return The Base64-encoded object
	 * @since 1.4
	 */
	public static String encodeObject( java.io.Serializable serializableObject )
	{
		return encodeObject( serializableObject, NO_OPTIONS );
	}   // end encodeObject
	


	/**
	 * Serializes an object and returns the Base64-encoded
	 * version of that serialized object. If the object
	 * cannot be serialized or there is another error,
	 * the method will return <tt>null</tt>.
	 * <p>
	 * Valid options:<pre>
	 *   GZIP: gzip-compresses object before encoding it.
	 *   DONT_BREAK_LINES: don't break lines at 76 characters
	 *     <i>Note: Technically, this makes your encoding non-compliant.</i>
	 * </pre>
	 * <p>
	 * Example: <code>encodeObject( myObj, Base64.GZIP )</code> or
	 * <p>
	 * Example: <code>encodeObject( myObj, Base64.GZIP | Base64.DONT_BREAK_LINES )</code>
	 *
	 * @param serializableObject The object to encode
	 * @param options Specified options
	 * @return The Base64-encoded object
	 * @see Base64#GZIP
	 * @see Base64#DONT_BREAK_LINES
	 * @since 2.0
	 */
	public static String encodeObject( java.io.Serializable serializableObject, int options )
	{
		// Streams
		java.io.ByteArrayOutputStream  baos  = null; 
		java.io.OutputStream           b64os = null; 
		java.io.ObjectOutputStream     oos   = null; 
		java.util.zip.GZIPOutputStream gzos  = null;
		
		// Isolate options
		int gzip           = (options & GZIP);
		
		try
		{
			// ObjectOutputStream -> (GZIP) -> Base64 -> ByteArrayOutputStream
			baos  = new java.io.ByteArrayOutputStream();
			b64os = new Base64.OutputStream( baos, ENCODE | options );
	
			// GZip?
			if( gzip == GZIP )
			{
				gzos = new java.util.zip.GZIPOutputStream( b64os );
				oos  = new java.io.ObjectOutputStream( gzos );
			}   // end if: gzip
			else
				oos   = new java.io.ObjectOutputStream( b64os );
			
			oos.writeObject( serializableObject );
		}   // end try
		catch( java.io.IOException e )
		{
			e.printStackTrace();
			return null;
		}   // end catch
		finally
		{
			try {
				close(oos);
			} catch (Exception e) {
				// ignore
			}
			try {
				close(gzos);
			} catch (Exception e) {
				// ignore
			}
			try {
				close(b64os);
			} catch (Exception e) {
				// ignore
			}
			try {
				close(baos);
			} catch (Exception e) {
				// ignore
			}
		}   // end finally
		
		// Return value according to relevant encoding.
		try 
		{
			return new String( baos.toByteArray(), PREFERRED_ENCODING );
		}   // end try
		catch (java.io.UnsupportedEncodingException uue)
		{
			return new String( baos.toByteArray() );
		}   // end catch
		
	}   // end encode
	
	

	/**
	 * Encodes a byte array into Base64 notation.
	 * Does not GZip-compress data.
	 *
	 * @param source The data to convert
	 * @since 1.4
	 */
	public static String encodeBytes( byte[] source )
	{
		return encodeBytes( source, 0, source.length, NO_OPTIONS );
	}   // end encodeBytes
	


	/**
	 * Encodes a byte array into Base64 notation.
	 * <p>
	 * Valid options:<pre>
	 *   GZIP: gzip-compresses object before encoding it.
	 *   DONT_BREAK_LINES: don't break lines at 76 characters
	 *     <i>Note: Technically, this makes your encoding non-compliant.</i>
	 * </pre>
	 * <p>
	 * Example: <code>encodeBytes( myData, Base64.GZIP )</code> or
	 * <p>
	 * Example: <code>encodeBytes( myData, Base64.GZIP | Base64.DONT_BREAK_LINES )</code>
	 *
	 *
	 * @param source The data to convert
	 * @param options Specified options
	 * @see Base64#GZIP
	 * @see Base64#DONT_BREAK_LINES
	 * @since 2.0
	 */
	public static String encodeBytes( byte[] source, int options )
	{   
		return encodeBytes( source, 0, source.length, options );
	}   // end encodeBytes
	
	
	/**
	 * Encodes a byte array into Base64 notation.
	 * Does not GZip-compress data.
	 *
	 * @param source The data to convert
	 * @param off Offset in array where conversion should begin
	 * @param len Length of data to convert
	 * @since 1.4
	 */
	public static String encodeBytes( byte[] source, int off, int len )
	{
		return encodeBytes( source, off, len, NO_OPTIONS );
	}   // end encodeBytes
	
	

	/**
	 * Encodes a byte array into Base64 notation.
	 * <p>
	 * Valid options:<pre>
	 *   GZIP: gzip-compresses object before encoding it.
	 *   DONT_BREAK_LINES: don't break lines at 76 characters
	 *     <i>Note: Technically, this makes your encoding non-compliant.</i>
	 * </pre>
	 * <p>
	 * Example: <code>encodeBytes( myData, Base64.GZIP )</code> or
	 * <p>
	 * Example: <code>encodeBytes( myData, Base64.GZIP | Base64.DONT_BREAK_LINES )</code>
	 *
	 *
	 * @param source The data to convert
	 * @param off Offset in array where conversion should begin
	 * @param len Length of data to convert
	 * @param options Specified options
	 * @param options alphabet type is pulled from this (standard, url-safe, ordered)
	 * @see Base64#GZIP
	 * @see Base64#DONT_BREAK_LINES
	 * @since 2.0
	 */
	public static String encodeBytes( byte[] source, int off, int len, int options )
	{
		// Isolate options
		int dontBreakLines = ( options & DONT_BREAK_LINES );
		int gzip           = ( options & GZIP   );
		
		// Compress?
		if( gzip == GZIP )
		{
			java.io.ByteArrayOutputStream  baos  = null;
			java.util.zip.GZIPOutputStream gzos  = null;
			Base64.OutputStream            b64os = null;
			
	
			try
			{
				// GZip -> Base64 -> ByteArray
				baos = new java.io.ByteArrayOutputStream();
				b64os = new Base64.OutputStream( baos, ENCODE | options );
				gzos  = new java.util.zip.GZIPOutputStream( b64os ); 
			
				gzos.write( source, off, len );
				close(gzos);
			}   // end try
			catch( java.io.IOException e )
			{
				e.printStackTrace();
				return null;
			}   // end catch
			finally
			{
				try {
					close(gzos);
				} catch (Exception e) {
					// ignore
				}
				try {
					close(b64os);
				} catch (Exception e) {
					// ignore
				}
				try {
					close(baos);
				} catch (Exception e) {
					// ignore
				}
			}   // end finally

			// Return value according to relevant encoding.
			try
			{
				return new String( baos.toByteArray(), PREFERRED_ENCODING );
			}   // end try
			catch (java.io.UnsupportedEncodingException uue)
			{
				return new String( baos.toByteArray() );
			}   // end catch
		}   // end if: compress
		
		// Else, don't compress. Better not to use streams at all then.
		else
		{
			// Convert option to boolean in way that code likes it.
			boolean breakLines = dontBreakLines == 0;
			
			int    len43   = len * 4 / 3;
			byte[] outBuff = new byte[   ( len43 )                      // Main 4:3
									   + ( (len % 3) > 0 ? 4 : 0 )      // Account for padding
									   + (breakLines ? ( len43 / MAX_LINE_LENGTH ) : 0) ]; // New lines      
			int d = 0;
			int e = 0;
			int len2 = len - 2;
			int lineLength = 0;
			for( ; d < len2; d+=3, e+=4 )
			{
				encode3to4( source, d+off, 3, outBuff, e, options );

				lineLength += 4;
				if( breakLines && lineLength == MAX_LINE_LENGTH )
				{   
					outBuff[e+4] = NEW_LINE;
					e++;
					lineLength = 0;
				}   // end if: end of line
			}   // en dfor: each piece of array

			if( d < len )
			{
				encode3to4( source, d+off, len - d, outBuff, e, options );
				e += 4;
			}   // end if: some padding needed

			
			// Return value according to relevant encoding.
			try
			{
				return new String( outBuff, 0, e, PREFERRED_ENCODING );
			}   // end try
			catch (java.io.UnsupportedEncodingException uue)
			{
				return new String( outBuff, 0, e );
			}   // end catch
			
		}   // end else: don't compress
		
	}   // end encodeBytes
	

	
	
	
/* ********  D E C O D I N G   M E T H O D S  ******** */
	
	
	/**
	 * Decodes four bytes from array <var>source</var>
	 * and writes the resulting bytes (up to three of them)
	 * to <var>destination</var>.
	 * The source and destination arrays can be manipulated
	 * anywhere along their length by specifying 
	 * <var>srcOffset</var> and <var>destOffset</var>.
	 * This method does not check to make sure your arrays
	 * are large enough to accomodate <var>srcOffset</var> + 4 for
	 * the <var>source</var> array or <var>destOffset</var> + 3 for
	 * the <var>destination</var> array.
	 * This method returns the actual number of bytes that 
	 * were converted from the Base64 encoding.
	 * <p>This is the lowest level of the decoding methods with
	 * all possible parameters.</p>
	 * 
	 *
	 * @param source the array to convert
	 * @param srcOffset the index where conversion begins
	 * @param destination the array to hold the conversion
	 * @param destOffset the index where output will be put
	 * @param options alphabet type is pulled from this (standard, url-safe, ordered)
	 * @return the number of decoded bytes converted
	 * @since 1.3
	 */
	private static int decode4to3( byte[] source, int srcOffset, byte[] destination, int destOffset, int options )
	{
		byte[] DECODABET = getDecodabet( options ); 
	
		// Example: Dk==
		if( source[ srcOffset + 2] == EQUALS_SIGN )
		{
			// Two ways to do the same thing. Don't know which way I like best.
			//int outBuff =   ( ( DECODABET[ source[ srcOffset    ] ] << 24 ) >>>  6 )
			//              | ( ( DECODABET[ source[ srcOffset + 1] ] << 24 ) >>> 12 );
			int outBuff =   ( ( DECODABET[ source[ srcOffset    ] ] & 0xFF ) << 18 )
						  | ( ( DECODABET[ source[ srcOffset + 1] ] & 0xFF ) << 12 );
			
			destination[ destOffset ] = (byte)( outBuff >>> 16 );
			return 1;
		}
		
		// Example: DkL=
		else if( source[ srcOffset + 3 ] == EQUALS_SIGN )
		{
			// Two ways to do the same thing. Don't know which way I like best.
			//int outBuff =   ( ( DECODABET[ source[ srcOffset     ] ] << 24 ) >>>  6 )
			//              | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 )
			//              | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 );
			int outBuff =   ( ( DECODABET[ source[ srcOffset     ] ] & 0xFF ) << 18 )
						  | ( ( DECODABET[ source[ srcOffset + 1 ] ] & 0xFF ) << 12 )
						  | ( ( DECODABET[ source[ srcOffset + 2 ] ] & 0xFF ) <<  6 );
			
			destination[ destOffset     ] = (byte)( outBuff >>> 16 );
			destination[ destOffset + 1 ] = (byte)( outBuff >>>  8 );
			return 2;
		}
		
		// Example: DkLE
		else
		{
			try{
			// Two ways to do the same thing. Don't know which way I like best.
			//int outBuff =   ( ( DECODABET[ source[ srcOffset     ] ] << 24 ) >>>  6 )
			//              | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 )
			//              | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 )
			//              | ( ( DECODABET[ source[ srcOffset + 3 ] ] << 24 ) >>> 24 );
			int outBuff =   ( ( DECODABET[ source[ srcOffset     ] ] & 0xFF ) << 18 )
						  | ( ( DECODABET[ source[ srcOffset + 1 ] ] & 0xFF ) << 12 )
						  | ( ( DECODABET[ source[ srcOffset + 2 ] ] & 0xFF ) <<  6)
						  | ( ( DECODABET[ source[ srcOffset + 3 ] ] & 0xFF )      );

			
			destination[ destOffset     ] = (byte)( outBuff >> 16 );
			destination[ destOffset + 1 ] = (byte)( outBuff >>  8 );
			destination[ destOffset + 2 ] = (byte)( outBuff       );

			return 3;
			}catch( Exception e){
				System.out.println(""+source[srcOffset]+ ": " + ( DECODABET[ source[ srcOffset     ] ]  ) );
				System.out.println(""+source[srcOffset+1]+  ": " + ( DECODABET[ source[ srcOffset + 1 ] ]  ) );
				System.out.println(""+source[srcOffset+2]+  ": " + ( DECODABET[ source[ srcOffset + 2 ] ]  ) );
				System.out.println(""+source[srcOffset+3]+  ": " + ( DECODABET[ source[ srcOffset + 3 ] ]  ) );
				return -1;
			}   // end catch
		}
	}   // end decodeToBytes
	
	
	
	
	/**
	 * Very low-level access to decoding ASCII characters in
	 * the form of a byte array. Does not support automatically
	 * gunzipping or any other "fancy" features.
	 *
	 * @param source The Base64 encoded data
	 * @param off    The offset of where to begin decoding
	 * @param len    The length of characters to decode
	 * @return decoded data
	 * @since 1.3
	 */
	public static byte[] decode( byte[] source, int off, int len, int options )
	{
		byte[] DECODABET = getDecodabet( options );
	
		int    len34   = len * 3 / 4;
		byte[] outBuff = new byte[ len34 ]; // Upper limit on size of output
		int    outBuffPosn = 0;
		
		byte[] b4        = new byte[4];
		int    b4Posn    = 0;
		int    i         = 0;
		byte   sbiCrop   = 0;
		byte   sbiDecode = 0;
		for( i = off; i < off+len; i++ )
		{
			sbiCrop = (byte)(source[i] & 0x7f); // Only the low seven bits
			sbiDecode = DECODABET[ sbiCrop ];
			
			if( sbiDecode >= WHITE_SPACE_ENC ) // White space, Equals sign or better
			{
				if( sbiDecode >= EQUALS_SIGN_ENC )
				{
					b4[ b4Posn++ ] = sbiCrop;
					if( b4Posn > 3 )
					{
						outBuffPosn += decode4to3( b4, 0, outBuff, outBuffPosn, options );
						b4Posn = 0;
						
						// If that was the equals sign, break out of 'for' loop
						if( sbiCrop == EQUALS_SIGN )
							break;
					}   // end if: quartet built
					
				}   // end if: equals sign or better
				
			}   // end if: white space, equals sign or better
			else
			{
				System.err.println( "Bad Base64 input character at " + i + ": " + source[i] + "(decimal)" );
				return null;
			}   // end else: 
		}   // each input character
								   
		byte[] out = new byte[ outBuffPosn ];
		System.arraycopy( outBuff, 0, out, 0, outBuffPosn ); 
		return out;
	}   // end decode
	
	
	
	
	/**
	 * Decodes data from Base64 notation, automatically
	 * detecting gzip-compressed data and decompressing it.
	 *
	 * @param s the string to decode
	 * @return the decoded data
	 * @since 1.4
	 */
	public static byte[] decode( String s )
	{
		return decode( s, NO_OPTIONS );
	}
	
	
	/**
	 * Decodes data from Base64 notation, automatically
	 * detecting gzip-compressed data and decompressing it.
	 *
	 * @param s the string to decode
	 * @param options encode options such as URL_SAFE
	 * @return the decoded data
	 * @since 1.4
	 */
	public static byte[] decode( String s, int options )
	{   
		byte[] bytes;
		try
		{
			bytes = s.getBytes( PREFERRED_ENCODING );
		}   // end try
		catch( java.io.UnsupportedEncodingException uee )
		{
			bytes = s.getBytes();
		}   // end catch
		//</change>
		
		// Decode
		bytes = decode( bytes, 0, bytes.length, options );
		
		
		// Check to see if it's gzip-compressed
		// GZIP Magic Two-Byte Number: 0x8b1f (35615)
		if( bytes != null && bytes.length >= 4 )
		{
			
			int head = (bytes[0] & 0xff) | ((bytes[1] << 8) & 0xff00);       
			if( java.util.zip.GZIPInputStream.GZIP_MAGIC == head ) 
			{
				java.io.ByteArrayInputStream  bais = null;
				java.util.zip.GZIPInputStream gzis = null;
				java.io.ByteArrayOutputStream baos = null;
				byte[] buffer = new byte[2048];
				int    length = 0;

				try
				{
					baos = new java.io.ByteArrayOutputStream();
					bais = new java.io.ByteArrayInputStream( bytes );
					gzis = new java.util.zip.GZIPInputStream( bais );

					while( ( length = gzis.read( buffer ) ) >= 0 )
					{
						baos.write(buffer,0,length);
					}   // end while: reading input

					// No error? Get new bytes.
					bytes = baos.toByteArray();

				}   // end try
				catch( java.io.IOException e )
				{
					// Just return originally-decoded bytes
				}   // end catch
				finally
				{
					try {
						close(baos);
					} catch (Exception e) {
						// ignore
					}
					try {
						close(gzis);
					} catch (Exception e) {
						// ignore
					}
					try {
						close(bais);
					} catch (Exception e) {
						// ignore
					}
				}   // end finally

			}   // end if: gzipped
		}   // end if: bytes.length >= 2
		
		return bytes;
	}   // end decode


	

	/**
	 * Attempts to decode Base64 data and deserialize a Java
	 * Object within. Returns <tt>null</tt> if there was an error.
	 *
	 * @param encodedObject The Base64 data to decode
	 * @return The decoded and deserialized object
	 * @since 1.5
	 */
	public static Object decodeToObject( String encodedObject )
	{
		// Decode and gunzip if necessary
		byte[] objBytes = decode( encodedObject );
		
		java.io.ByteArrayInputStream  bais = null;
		java.io.ObjectInputStream     ois  = null;
		Object obj = null;
		
		try
		{
			bais = new java.io.ByteArrayInputStream( objBytes );
			ois  = new java.io.ObjectInputStream( bais );
		
			obj = ois.readObject();
		}   // end try
		catch( java.io.IOException e )
		{
			e.printStackTrace();
			obj = null;
		}   // end catch
		catch( java.lang.ClassNotFoundException e )
		{
			e.printStackTrace();
			obj = null;
		}   // end catch
		finally
		{
			try{ close(bais); } catch( Exception e ){}
			try{ close(ois);  } catch( Exception e ){}
		}   // end finally
		
		return obj;
	}   // end decodeObject
	
	
	
	/**
	 * Convenience method for encoding data to a file.
	 *
	 * @param dataToEncode byte array of data to encode in base64 form
	 * @param filename Filename for saving encoded data
	 * @return <tt>true</tt> if successful, <tt>false</tt> otherwise
	 *
	 * @since 2.1
	 */
	public static boolean encodeToFile( byte[] dataToEncode, String filename )
	{
		boolean success = false;
		Base64.OutputStream bos = null;
		try
		{
			bos = new Base64.OutputStream( 
					  new java.io.FileOutputStream( filename ), Base64.ENCODE );
			bos.write( dataToEncode );
			success = true;
		}   // end try
		catch( java.io.IOException e )
		{
			
			success = false;
		}   // end catch: IOException
		finally
		{
			try{ close(bos); } catch( Exception e ){}
		}   // end finally
		
		return success;
	}   // end encodeToFile
	
	
	/**
	 * Convenience method for decoding data to a file.
	 *
	 * @param dataToDecode Base64-encoded data as a string
	 * @param filename Filename for saving decoded data
	 * @return <tt>true</tt> if successful, <tt>false</tt> otherwise
	 *
	 * @since 2.1
	 */
	public static boolean decodeToFile( String dataToDecode, String filename )
	{
		boolean success = false;
		Base64.OutputStream bos = null;
		try
		{
				bos = new Base64.OutputStream( 
						  new java.io.FileOutputStream( filename ), Base64.DECODE );
				bos.write( dataToDecode.getBytes( PREFERRED_ENCODING ) );
				success = true;
		}   // end try
		catch( java.io.IOException e )
		{
			success = false;
		}   // end catch: IOException
		finally
		{
				try{ close(bos); } catch( Exception e ){}
		}   // end finally
		
		return success;
	}   // end decodeToFile
	
	
	
	
	/**
	 * Convenience method for reading a base64-encoded
	 * file and decoding it.
	 *
	 * @param filename Filename for reading encoded data
	 * @return decoded byte array or null if unsuccessful
	 *
	 * @since 2.1
	 */
	public static byte[] decodeFromFile( String filename )
	{
		byte[] decodedData = null;
		Base64.InputStream bis = null;
		try
		{
			// Set up some useful variables
			java.io.File file = new java.io.File( filename );
			byte[] buffer = null;
			int length   = 0;
			int numBytes = 0;
			
			// Check for size of file
			if( file.length() > Integer.MAX_VALUE )
			{
				System.err.println( "File is too big for this convenience method (" + file.length() + " bytes)." );
				return null;
			}   // end if: file too big for int index
			buffer = new byte[ (int)file.length() ];
			
			// Open a stream
			bis = new Base64.InputStream( 
					  new java.io.BufferedInputStream( 
					  new java.io.FileInputStream( file ) ), Base64.DECODE );
			
			// Read until done
			while( ( numBytes = bis.read( buffer, length, 4096 ) ) >= 0 )
				length += numBytes;
			
			// Save in a variable to return
			decodedData = new byte[ length ];
			System.arraycopy( buffer, 0, decodedData, 0, length );
			
		}   // end try
		catch( java.io.IOException e )
		{
			System.err.println( "Error decoding from file " + filename );
		}   // end catch: IOException
		finally
		{
			try{ close(bis); } catch( Exception e) {}
		}   // end finally
		
		return decodedData;
	}   // end decodeFromFile
	
	
	
	/**
	 * Convenience method for reading a binary file
	 * and base64-encoding it.
	 *
	 * @param filename Filename for reading binary data
	 * @return base64-encoded string or null if unsuccessful
	 *
	 * @since 2.1
	 */
	public static String encodeFromFile( String filename )
	{
		String encodedData = null;
		Base64.InputStream bis = null;
		try
		{
			// Set up some useful variables
			java.io.File file = new java.io.File( filename );
			byte[] buffer = new byte[ Math.max((int)(file.length() * 1.4),40) ]; // Need max() for math on small files (v2.2.1)
			int length   = 0;
			int numBytes = 0;
			
			// Open a stream
			bis = new Base64.InputStream( 
					  new java.io.BufferedInputStream( 
					  new java.io.FileInputStream( file ) ), Base64.ENCODE );
			
			// Read until done
			while( ( numBytes = bis.read( buffer, length, 4096 ) ) >= 0 )
				length += numBytes;
			
			// Save in a variable to return
			encodedData = new String( buffer, 0, length, Base64.PREFERRED_ENCODING );
				
		}   // end try
		catch( java.io.IOException e )
		{
			System.err.println( "Error encoding from file " + filename );
		}   // end catch: IOException
		finally
		{
			try{ close(bis); } catch( Exception e) {}
		}   // end finally
		
		return encodedData;
		}   // end encodeFromFile
	
	
	
	
	/**
	 * Reads <tt>infile</tt> and encodes it to <tt>outfile</tt>.
	 *
	 * @param infile Input file
	 * @param outfile Output file
	 * @return true if the operation is successful
	 * @since 2.2
	 */
	public static boolean encodeFileToFile( String infile, String outfile )
	{
		boolean success = false;
		java.io.InputStream in = null;
		java.io.OutputStream out = null;
		try{
			in  = new Base64.InputStream( 
					  new java.io.BufferedInputStream( 
					  new java.io.FileInputStream( infile ) ), 
					  Base64.ENCODE );
			out = new java.io.BufferedOutputStream( new java.io.FileOutputStream( outfile ) );
			byte[] buffer = new byte[65536]; // 64K
			int read = -1;
			while( ( read = in.read(buffer) ) >= 0 ){
				out.write( buffer,0,read );
			}   // end while: through file
			success = true;
		} catch( java.io.IOException exc ){
			exc.printStackTrace();
		} finally{
			try {
				close(in);
			} catch (Exception exc) {
				// ignore
			}
			try {
				close(out);
			} catch (Exception exc) {
				// ignore
			}
		}   // end finally
		
		return success;
	}   // end encodeFileToFile
	
	
	
	/**
	 * Reads <tt>infile</tt> and decodes it to <tt>outfile</tt>.
	 *
	 * @param infile Input file
	 * @param outfile Output file
	 * @return true if the operation is successful
	 * @since 2.2
	 */
	public static boolean decodeFileToFile( String infile, String outfile )
	{
		boolean success = false;
		java.io.InputStream in = null;
		java.io.OutputStream out = null;
		try{
			in  = new Base64.InputStream( 
					  new java.io.BufferedInputStream( 
					  new java.io.FileInputStream( infile ) ), 
					  Base64.DECODE );
			out = new java.io.BufferedOutputStream( new java.io.FileOutputStream( outfile ) );
			byte[] buffer = new byte[65536]; // 64K
			int read = -1;
			while( ( read = in.read(buffer) ) >= 0 ){
				out.write( buffer,0,read );
			}   // end while: through file
			success = true;
		} catch( java.io.IOException exc ){
			exc.printStackTrace();
		} finally{
			try {
				close(in);
			} catch (Exception exc) {
				// ignore
			}
			try {
				close(out);
			} catch (Exception exc) {
				// ignore
			}
		}   // end finally
		
		return success;
	}   // end decodeFileToFile
	
	
	private static void close(Closeable closeable) throws IOException {
		if (closeable != null) {
			closeable.close();
		}
	}


	/* ********  I N N E R   C L A S S   I N P U T S T R E A M  ******** */
	
	
	
	/**
	 * A {@link Base64.InputStream} will read data from another
	 * <tt>java.io.InputStream</tt>, given in the constructor,
	 * and encode/decode to/from Base64 notation on the fly.
	 *
	 * @see Base64
	 * @since 1.3
	 */
	public static class InputStream extends java.io.FilterInputStream
	{
		private boolean encode;         // Encoding or decoding
		private int     position;       // Current position in the buffer
		private byte[]  buffer;         // Small buffer holding converted data
		private int     bufferLength;   // Length of buffer (3 or 4)
		private int     numSigBytes;    // Number of meaningful bytes in the buffer
		private int     lineLength;
		private boolean breakLines;     // Break lines at less than 80 characters
		private int     options;        // Record options used to create the stream.
		@SuppressWarnings("unused")
		private byte[]  alphabet;	    // Local copies to avoid extra method calls
		private byte[]  decodabet;		// Local copies to avoid extra method calls
		
		
		/**
		 * Constructs a {@link Base64.InputStream} in DECODE mode.
		 *
		 * @param in the <tt>java.io.InputStream</tt> from which to read data.
		 * @since 1.3
		 */
		public InputStream( java.io.InputStream in )
		{   
			this( in, DECODE );
		}   // end constructor
		
		
		/**
		 * Constructs a {@link Base64.InputStream} in
		 * either ENCODE or DECODE mode.
		 * <p>
		 * Valid options:<pre>
		 *   ENCODE or DECODE: Encode or Decode as data is read.
		 *   DONT_BREAK_LINES: don't break lines at 76 characters
		 *     (only meaningful when encoding)
		 *     <i>Note: Technically, this makes your encoding non-compliant.</i>
		 * </pre>
		 * <p>
		 * Example: <code>new Base64.InputStream( in, Base64.DECODE )</code>
		 *
		 *
		 * @param in the <tt>java.io.InputStream</tt> from which to read data.
		 * @param options Specified options
		 * @see Base64#ENCODE
		 * @see Base64#DECODE
		 * @see Base64#DONT_BREAK_LINES
		 * @since 2.0
		 */
		public InputStream( java.io.InputStream in, int options )
		{   
			super( in );
			this.breakLines   = (options & DONT_BREAK_LINES) != DONT_BREAK_LINES;
			this.encode       = (options & ENCODE) == ENCODE;
			this.bufferLength = encode ? 4 : 3;
			this.buffer       = new byte[ bufferLength ];
			this.position     = -1;
			this.lineLength   = 0;
			this.options      = options; // Record for later, mostly to determine which alphabet to use
			this.alphabet     = getAlphabet(options);
			this.decodabet    = getDecodabet(options);
		}   // end constructor
		
		/**
		 * Reads enough of the input stream to convert
		 * to/from Base64 and returns the next byte.
		 *
		 * @return next byte
		 * @since 1.3
		 */
		@Override
		public int read() throws java.io.IOException 
		{ 
			// Do we need to get data?
			if( position < 0 )
			{
				if( encode )
				{
					byte[] b3 = new byte[3];
					int numBinaryBytes = 0;
					for( int i = 0; i < 3; i++ )
					{
						try
						{ 
							int b = in.read();
							
							// If end of stream, b is -1.
							if( b >= 0 )
							{
								b3[i] = (byte)b;
								numBinaryBytes++;
							}   // end if: not end of stream
							
						}   // end try: read
						catch( java.io.IOException e )
						{   
							// Only a problem if we got no data at all.
							if( i == 0 )
								throw e;
							
						}   // end catch
					}   // end for: each needed input byte
					
					if( numBinaryBytes > 0 )
					{
						encode3to4( b3, 0, numBinaryBytes, buffer, 0, options );
						position = 0;
						numSigBytes = 4;
					}   // end if: got data
					else
					{
						return -1;
					}   // end else
				}   // end if: encoding
				
				// Else decoding
				else
				{
					byte[] b4 = new byte[4];
					int i = 0;
					for( i = 0; i < 4; i++ )
					{
						// Read four "meaningful" bytes:
						int b = 0;
						do{ b = in.read(); }
						while( b >= 0 && decodabet[ b & 0x7f ] <= WHITE_SPACE_ENC );
						
						if( b < 0 )
							break; // Reads a -1 if end of stream
						
						b4[i] = (byte)b;
					}   // end for: each needed input byte
					
					if( i == 4 )
					{
						numSigBytes = decode4to3( b4, 0, buffer, 0, options );
						position = 0;
					}   // end if: got four characters
					else if( i == 0 ){
						return -1;
					}   // end else if: also padded correctly
					else
					{
						// Must have broken out from above.
						throw new java.io.IOException( "Improperly padded Base64 input." );
					}   // end 
					
				}   // end else: decode
			}   // end else: get data
			
			// Got data?
			if( position >= 0 ) // lgtm [java/constant-comparison]
			{
				// End of relevant data?
				if( /*!encode &&*/ position >= numSigBytes )
					return -1;
				
				if( encode && breakLines && lineLength >= MAX_LINE_LENGTH )
				{
					lineLength = 0;
					return '\n';
				}   // end if
				else
				{
					lineLength++;   // This isn't important when decoding
									// but throwing an extra "if" seems
									// just as wasteful.
					
					int b = buffer[ position++ ];

					if( position >= bufferLength )
						position = -1;

					return b & 0xFF; // This is how you "cast" a byte that's
									 // intended to be unsigned.
				}   // end else
			}   // end if: position >= 0
			
			// Else error
			else
			{   
				// When JDK1.4 is more accepted, use an assertion here.
				throw new java.io.IOException( "Error in Base64 code reading stream." );
			}   // end else
		}   // end read
		
		
		/**
		 * Calls {@link #read()} repeatedly until the end of stream
		 * is reached or <var>len</var> bytes are read.
		 * Returns number of bytes read into array or -1 if
		 * end of stream is encountered.
		 *
		 * @param dest array to hold values
		 * @param off offset for array
		 * @param len max number of bytes to read into array
		 * @return bytes read into array or -1 if end of stream is encountered.
		 * @since 1.3
		 */
		@Override
		public int read( byte[] dest, int off, int len ) throws java.io.IOException
		{
			int i;
			int b;
			for( i = 0; i < len; i++ )
			{
				b = read();
				
				//if( b < 0 && i == 0 )
				//    return -1;
				
				if( b >= 0 )
					dest[off + i] = (byte)b;
				else if( i == 0 )
					return -1;
				else
					break; // Out of 'for' loop
			}   // end for: each byte read
			return i;
		}   // end read
		
	}   // end inner class InputStream
	
	
	
	
	
	
	/* ********  I N N E R   C L A S S   O U T P U T S T R E A M  ******** */
	
	
	
	/**
	 * A {@link Base64.OutputStream} will write data to another
	 * <tt>java.io.OutputStream</tt>, given in the constructor,
	 * and encode/decode to/from Base64 notation on the fly.
	 *
	 * @see Base64
	 * @since 1.3
	 */
	public static class OutputStream extends java.io.FilterOutputStream
	{
		private boolean encode;
		private int     position;
		private byte[]  buffer;
		private int     bufferLength;
		private int     lineLength;
		private boolean breakLines;
		private byte[]  b4; // Scratch used in a few places
		private boolean suspendEncoding;
		private int options; // Record for later
		@SuppressWarnings("unused")
		private byte[]  alphabet;	    // Local copies to avoid extra method calls
		private byte[]  decodabet;		// Local copies to avoid extra method calls
		
		/**
		 * Constructs a {@link Base64.OutputStream} in ENCODE mode.
		 *
		 * @param out the <tt>java.io.OutputStream</tt> to which data will be written.
		 * @since 1.3
		 */
		public OutputStream( java.io.OutputStream out )
		{   
			this( out, ENCODE );
		}   // end constructor
		
		
		/**
		 * Constructs a {@link Base64.OutputStream} in
		 * either ENCODE or DECODE mode.
		 * <p>
		 * Valid options:<pre>
		 *   ENCODE or DECODE: Encode or Decode as data is read.
		 *   DONT_BREAK_LINES: don't break lines at 76 characters
		 *     (only meaningful when encoding)
		 *     <i>Note: Technically, this makes your encoding non-compliant.</i>
		 * </pre>
		 * <p>
		 * Example: <code>new Base64.OutputStream( out, Base64.ENCODE )</code>
		 *
		 * @param out the <tt>java.io.OutputStream</tt> to which data will be written.
		 * @param options Specified options.
		 * @see Base64#ENCODE
		 * @see Base64#DECODE
		 * @see Base64#DONT_BREAK_LINES
		 * @since 1.3
		 */
		public OutputStream( java.io.OutputStream out, int options )
		{   
			super( out );
			this.breakLines   = (options & DONT_BREAK_LINES) != DONT_BREAK_LINES;
			this.encode       = (options & ENCODE) == ENCODE;
			this.bufferLength = encode ? 3 : 4;
			this.buffer       = new byte[ bufferLength ];
			this.position     = 0;
			this.lineLength   = 0;
			this.suspendEncoding = false;
			this.b4           = new byte[4];
			this.options      = options;
			this.alphabet     = getAlphabet(options);
			this.decodabet    = getDecodabet(options);
		}   // end constructor
		
		
		/**
		 * Writes the byte to the output stream after
		 * converting to/from Base64 notation.
		 * When encoding, bytes are buffered three
		 * at a time before the output stream actually
		 * gets a write() call.
		 * When decoding, bytes are buffered four
		 * at a time.
		 *
		 * @param theByte the byte to write
		 * @since 1.3
		 */
		@Override
		public void write(int theByte) throws java.io.IOException
		{
			// Encoding suspended?
			if( suspendEncoding )
			{
				super.out.write( theByte );
				return;
			}   // end if: supsended
			
			// Encode?
			if( encode )
			{
				buffer[ position++ ] = (byte)theByte;
				if( position >= bufferLength )  // Enough to encode.
				{
					out.write( encode3to4( b4, buffer, bufferLength, options ) );

					lineLength += 4;
					if( breakLines && lineLength >= MAX_LINE_LENGTH )
					{
						out.write( NEW_LINE );
						lineLength = 0;
					}   // end if: end of line

					position = 0;
				}   // end if: enough to output
			}   // end if: encoding

			// Else, Decoding
			else
			{
				// Meaningful Base64 character?
				if( decodabet[ theByte & 0x7f ] > WHITE_SPACE_ENC )
				{
					buffer[ position++ ] = (byte)theByte;
					if( position >= bufferLength )  // Enough to output.
					{
						int len = Base64.decode4to3( buffer, 0, b4, 0, options );
						out.write( b4, 0, len );
						//out.write( Base64.decode4to3( buffer ) );
						position = 0;
					}   // end if: enough to output
				}   // end if: meaningful base64 character
				else if( decodabet[ theByte & 0x7f ] != WHITE_SPACE_ENC )
				{
					throw new java.io.IOException( "Invalid character in Base64 data." );
				}   // end else: not white space either
			}   // end else: decoding
		}   // end write
		
		
		
		/**
		 * Calls {@link #write(int)} repeatedly until <var>len</var> 
		 * bytes are written.
		 *
		 * @param theBytes array from which to read bytes
		 * @param off offset for array
		 * @param len max number of bytes to read into array
		 * @since 1.3
		 */
		@Override
		public void write( byte[] theBytes, int off, int len ) throws java.io.IOException
		{
			// Encoding suspended?
			if( suspendEncoding )
			{
				super.out.write( theBytes, off, len );
				return;
			}   // end if: supsended
			
			for( int i = 0; i < len; i++ )
			{
				write( theBytes[ off + i ] );
			}   // end for: each byte written
			
		}   // end write
		
		
		
		/**
		 * Method added by PHIL. [Thanks, PHIL. -Rob]
		 * This pads the buffer without closing the stream.
		 */
		public void flushBase64() throws java.io.IOException 
		{
			if( position > 0 )
			{
				if( encode )
				{
					out.write( encode3to4( b4, buffer, position, options ) );
					position = 0;
				}   // end if: encoding
				else
				{
					throw new java.io.IOException( "Base64 input not properly padded." );
				}   // end else: decoding
			}   // end if: buffer partially full

		}   // end flush

		
		/** 
		 * Flushes and closes (I think, in the superclass) the stream. 
		 *
		 * @since 1.3
		 */
		@Override
		public void close() throws java.io.IOException
		{
			// 1. Ensure that pending characters are written
			flushBase64();

			// 2. Actually close the stream
			// Base class both flushes and closes.
			super.close();
			
			buffer = null;
			out    = null;
		}   // end close
		
		
		
		/**
		 * Suspends encoding of the stream.
		 * May be helpful if you need to embed a piece of
		 * base640-encoded data in a stream.
		 *
		 * @since 1.5.1
		 */
		public void suspendEncoding() throws java.io.IOException 
		{
			flushBase64();
			this.suspendEncoding = true;
		}   // end suspendEncoding
		
		
		/**
		 * Resumes encoding of the stream.
		 * May be helpful if you need to embed a piece of
		 * base640-encoded data in a stream.
		 *
		 * @since 1.5.1
		 */
		public void resumeEncoding()
		{
			this.suspendEncoding = false;
		}   // end resumeEncoding
		
		
		
	}   // end inner class OutputStream
	
	
}   // end class Base64
